Efficient harvesting of the near-infrared (NIR) portion of the sunlight remains key to the development of a solar-to-fuel renewable energy infrastructure. Here we report on the development of first pristine plasmonic nanoparticle-assisted NIR-II photon-to-hydrogen production strategy that does not require any external electric bias or sacrificial chemicals. Our strategy utilizes a robust and easily scalable plasmonic substrate containing pristine gold nanoprisms to drive photocatalytic Si–H activation in water, producing hydrogen and silanol. The photocatalytic substrate exhibited excellent photon-to-hydrogen conversion efficiency of ∼0.85–1.45% for wavelengths between 1000 and 1700 nm while producing hydrogen at 132 μL min–1 mg–1 Au. The robustness and easy scalability of our catalyst fabrication, ease of usage, excellent photon-to-hydrogen production efficiency, and no requirement of additional energy bias make our strategy highly relevant for applications in the alternative energy sector.